1. Technical Field
This invention relates to telecommunications. In particular, this invention relates to the updating of user presence information on a wireless messaging network.
2. Description of the Related Art
Many mobile communications devices are multi-functional and include wireless systems for both voice communications (radiotelephony) and packet data communications. The availability of voice and packet data services to the user of a mobile communication device depends, in part, on the received signal strength at the mobile device. In some situations, a mobile device user may not be available to participate in data or telephony communications, for example when the user's device is beyond the reach of a mobile communications network. In other situations, the received signal strength at the mobile device may be too weak to allow for voice or data communications to be initiated or continued.
While some mobile communication network provide “presence” services that may indicate to other users on the network whether a particular mobile user is available for voice or packet data communications according to the mobile user's reported status (for example, whether the user's mobile device is powered on or off, or whether the user has chosen to make him or herself unavailable for packet data communication), such presence services do not provide a complete solution to the problem of a mobile user who moves outside the network's coverage, or moves into a region where the signal strength is too weak to maintain a connection between the mobile device and the network. The mobile device user is typically not provided with advanced warning regarding impending signal loss; the user's first notification that the received signal strength has dropped below an acceptable threshold is typically the sudden termination of an ongoing voice call. Alternatively, there is generally no opportunity to provide advance notice to another party engaged in communication with the mobile device user that the user's mobile device is about to move outside of mobile communications network coverage or that the received signal strength at the mobile device is likely to drop below an acceptable level. This may prove frustrating to the mobile user and other parties communicating with the user, who may wish to be able to complete certain tasks requiring voice or data connectivity before the connection between the mobile device and the network is dropped.
It would accordingly be advantageous to provide a system and method a mobile device user or other network user may be notified of a pending loss of signal at the mobile device, or a change in presence or availability status on the network as a result of a pending loss of signal at the mobile device.